This study aimed to determine the eye movement parameter(s) that is primarily affected when fully sighted subjects use plus-lens magnifiers
Two forms of plus-lens magnifier were used: hand-held and spectacle-mounted. Eye movements
were recorded using an infrared limbal reflection system as subjects read passages of text with and without the magnifiers
. Data were compared for a young age
group and an elderly (education-matched) age
For both age
groups, a sawtooth pattern of eye movements
was observed and reading speed
was significantly (p = 0.0001) reduced when using the magnifiers
compared with reading
without. Forward saccade length decreased significantly (p = 0.0001) and time for retrace increased significantly (p = 0.0001), but fixation durations were unaffected. The form of magnifier had no significant effect on reading speed
or eye movement parameters.
The reduction in reading speed
that occurred when using the plus-lens magnifiers
was primarily a result of decreased forward saccade length.